The Caldecott Tunnel bores through the Oakland hills to connect the East Bay with Contra Costa County. It's a heavily traveled route which results in intense traffic snarls during commute hours. So now a fourth bore is being drilled to the tune of $420 million. During construction these imposing sound walls have been built to protect the housing development that faces the freeway from construction noise. Every time I see them I can't help but think of 2001: A Space Odyssey. Just last week, fossils were uncovered by the dig!